Canada #596iv, vi, x 20c Multicoloured Prairies, 1972-1979 Landscape Definitive Issue, 17 Fine & VF Used Singles 4 mm OP-2 Tagging, Comprehensive Run Of Smooth Paper Printings, Many Unlisted Fluorescence Levels, Different From Lot 352

17 Fine & VF used singles of the 20c multicoloured Prairies from the 1972-1979 Landscape Definitive Issue 4 mm OP-2 tagging, comprehensive run of smooth paper printings, many unlisted fluorescence levels, different from lot 352. Includes: (1) NF/NF paper; (2) NF/DF1 paper; (3) NF/DF2-fl paper; (4) DF2/NF paper; (5) DF2/DF1 paper; (6) DF2/DF2 paper; (7) DF2/LF3 paper; (8) as (7) but pale peachy orange fields; (9) DF2/F paper; (10) LF3/DF2 paper; (11) as (10) but pale peachy-orange fields; (12) LF3/LF3 paper, pale peachy orange fields; (13) as (12) but LF3/F paper; (14) LF4/LF3 paper; (15) LF4/LF4 paper, pale peachy-orange fields; (16) As (15) but LF4/MF6 paper; (17) HF9/HF8 paper; (18) as (17) but pale peachy orange fields.

Unitrade values this at $25.75, taking the unlisted varieties as the closest listed equivalent. The stamps offered here grade 70-84 as follows:

Centering/Margins: 30/60, 35/60, 40/60, 44/60

Paper Freshness: 5/5

Colour: 5/5

Impression: 5/5

Absence of Visible Paper Flaws: 5/5

Perforations: 10/10

Cancellation: 8/10 and 10/10

The landscape definitives of 1972-1979 are a particularly complex area, with many of the compexities not being listed in Unitrade. Unitrade's description of paper fluorescence is very oversimplified. We have described all the differences we see on these stamps, and in ascribing fluorescence levels we cross -referenced the stamps back to stamps of the Caricature issue that we had sorted into the various fluorescence levels earlier. As a result of this, some of my earlier descriptons have changed slightly, as I have made the determination of fluorescence more accurate. Another aspect that isn't covered in Unitrade, but which clearly differs is the appearance of the photogravure printed background on the 10c, 15c and 50c values. I have described them as "screened background", "semi-solid background", "nearly solid background" and solid background. Screened background, means that all the individual screening dots that make up the coloured area can all be clearly seen as individual dots. Semi-sold background refers to one where some dots are visible, but they are clearly merging into ine another. Nearly sold background means very few, individual dots are visible. Finally on stamps with solid background, the individual screening dots that make up the printing are not individually visible as dots.